Dealing with Woodchuck Damage
By Alan T. Eaton, Ph.D.
Extension Specialist, Integrated Pest Management
ter, or overwintering sites by many other animals. Cottontail rabbits, skunks, raccoons, foxes, coyotes, snakes, weasels, and chipmunks are among the animals that use
woodchuck burrows. Woodchucks are also prey for foxes
and coyotes, bobcats, fishers, eagles, and large hawks.
Woodchucks especially like to eat beans, peas, carrot
greens, alfalfa, clover, and grasses. They also eat cabbage,
broccoli, tomato, dandelion, and other plants. There are
few succulent plants that they won t eat. They also claw
up the trunks of newly planted apple trees, sometimes killing them (partly from burrowing right at the base). They
don t seem to prefer corn. They are most active early in
the morning and late in the afternoon.
Woodchucks are day-active animals that feed on a wide variety
of plants. This one is eating dandelions. Photo: A.T. Eaton
Woodchucks frequently damage plants in NH home
grounds and gardens. They mow down many garden
plants, and dig burrows which dry out the roots of trees.
Back when most NH people relied on horses, woodchucks
were scorned because their hidden holes could cause a horse
to trip and break a leg. No wonder we call them pests!
Before we paint them as entirely bad, we should recognize how woodchucks are valuable. They are native
mammals, evolved to fit into the environment here. They
dig extensive burrows that are used as escape cover, shel-
Many animals use burrows started by woodchucks, including
this red fox. Photo: A.T. Eaton
To control woodchuck damage, you should consider
non-lethal measures. That usually means fencing of some
sort. Since woodchucks can climb and burrow, the most
effective material is probably electric fencing. An effective combination is one wire 4 inches off the ground and a
second at 8 or 9 inches high. If squirrels are a problem,
they will easily jump over that, so you will need a third
strand about 6 to 8 inches above the second. Garden supply centers now have a wide assortment of plug-in and battery powered chargers that are easy to set up and take
down. Use a UL-approved charger for your fence. You
will also need to keep the electric fence clear of any ob-
Electric fencing has kept this research plot entirely free of woodchuck damage. Note that weeds must be kept from growing into
the fence. Photo: A.T. Eaton
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structions or vegetation that might short out the charge and
make it ineffective. Electric fences for woodchucks can be
low enough that you usually do not need a gate.
If you use non-electric fencing, buy a mesh size
smaller than 2 X 2 inches, especially close to the ground.
(The young ones can sometimes squeeze through that
mesh size.) Common chicken wire rusts away quickly
the woodchucks may push through it by the second growing season. Non-electric fencing should have some means
of preventing the woodchucks from burrowing underneath.
You could bury the fence to a depth of 10 or 12 inches. Or
you could bend the lower 1 foot 90 degrees outward, to
form an L , then lay it on the ground and securely pin the
L into the ground. Another option is laying an 18 inch
wide strip of galvanized fencing on the ground below the
fence, keeping the vertical fence flush with it.
Unless it is electrified, make your fence at least 3 feet
high. Bending the top 12 to 15 inches outward at about a
45 degree angle will help deter them from climbing a nonelectrified fence. (Yes, they do climb!) Another benefit
from fencing is that it keeps other things out of the garden —
porcupines (they like raspberries), snapping turtles (like to
lay eggs), dogs, kids on tricycles.
Don t neglect the gate. That is often the spot where
defenses are the weakest. If they try to burrow underneath,
install a board dug into the ground and flush with the bottom of the gate, or lay down a length of fencing as described above.
Frightening devices just don t seem to work well on
woodchucks, especially if you have luscious, tender vegetables to offer. Banging pie plates, shiny reflectors, and
ultrasonic noise emitters just don t seem to help. Scarecrows reportedly can offer temporary relief if they are
moved regularly and you incorporate a high level of human activity in the area. Some (short term) success has
An effective method of trapping without bait is to place the trap
with a barrier so that the animal has no choice but to go through
the trap, when it exits its burrow. A live trap permits the release
of non-target animals. Photo: A.T. Eaton
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Live trapping is not the “humane” treatment that most people
think. Please think twice before trapping! Photo: A.T. Eaton
been reported from having moving pinwheels in the garden. Another short term success has been reported from
scattering large clean jars of water in the garden. Presumably this works by projecting a distorted reflection of the
woodchuck entering the garden. Fencing the garden takes
slightly more effort, and is much more effective.
Live traps are a possibility in some situations, but the
recent overspread of rabies in most of New Hampshire
could make the use of live traps more of a risk now. If a
carrier of rabies were trapped, it could threaten anyone exposed. Rabies is almost always lethal to people (and other
mammals) once symptoms appear.
For those people vaccinated against rabies, live trapping might be less risky. The most effective technique is
to place the trap directly at the burrow entrance, and use a
barrier of boards or other material to direct the animal into
the trap. No bait is needed in this situation. The animal
just walks out of its burrow and into the trap. Trap placement elsewhere is much less effective, but sometimes the
woodchuck can be enticed inside with fresh apple slices or
fresh carrots or lettuce. Change baits daily.
Before you start live trapping, think carefully about
what you are going to do with the trapped animals. Translocating a woodchuck from its home is subjecting the humanely trapped animal to a prolonged, very stressful
ordeal that often ends in its death. Suitable habitat is farmland with open fields and an abundance of short grasses.
But farmers or gardeners are not likely to agree to your releasing animals on their property, and woodchucks are not
woodland creatures. The best use of live trapping may be
in early spring (before females give birth) combined with
humanely killing the trapped animals. Please think carefully before you trap!
We should probably consider lethal controls only as a
last resort. Woodchucks are important parts of the natural
environment, and should not be killed indiscriminately.
Also, some methods can end up killing other animals. If
you employ lethal controls, please do so cautiously, after
careful consideration. There are several methods:
Gas cartridges are cardboard cylinders filled with
slow-burning chemicals. Many garden supply centers sell
them. To use them, you locate all entrances of the
woodchuck s burrow. Make sure it is an active burrow,
and wait until you see the woodchuck go inside. Then seal
all entrances but one, and prepare a sod plug for the opening. Use a three or four foot branch to probe the burrow
for directional changes. Then tape the cartridge to the
branch, light the fuse, and place it well inside. Staghorn
sumac works well for this purpose. Then seal up the entrance thoroughly. The cartridge produces carbon monoxide, carbon dioxide and other lethal gasses, and will kill
the inhabitants. Be sure to confirm that this burrow is in
use by woodchucks, or you may kill other animals that
could be using the burrow. Most failures with cartridges
are from the fuses going out (often because loose dirt covered then, or they were thrown). Sometimes they fail because the woodchuck was somewhere else when the
burrow was fumigated. Upon its return, it just re-opens the
burrow. Never use a gas cartridge near flammables or under a wooden structure.
Shooting is an option that has a low risk of harming
non-target animals, if done carefully. In New Hampshire,
woodchucks can be shot by anyone with a hunting license,
or by farmers on their own property, protecting their crops.
The Division of Fish & Game does not consider home gardeners to be farmers. (In other words, home gardeners
who wish to shoot woodchucks must get a hunting license,
or find someone who is licensed.) The state laws allow us
to hunt woodchucks at any time of year. A .22 caliber rifle
with hollow point cartridge is the most commonly employed weapon for woodchuck control. When shooting,
you need to take extreme care that the area is safe for a
shot. A .22 caliber long rifle bullet can travel nearly a mile
if it does not strike something first. They also easily ricochet off hard surfaces.
If you can t handle the problem yourself, pest control
companies that might help are listed in the telephone book
under pest control services. Some of them specialize in
wildlife damage problems. Also, your regional office of
NH Dept. of Fish & Game can refer you to a nuisance
trapper, who can handle the problem for a fee.
We tested a capsaicin taste repellant on woodchucks
at the UNH campus in 1997. We offered our wild volunteers young broccoli and lettuce plants. In each of six trials, the animal had a choice between an untreated plant,
and one sprayed with a commercial capsaicin spray. We
saw no evidence that the capsaicin deterred the animals
from feeding.
If you can protect your valuable plants from them,
having woodchucks in the yard can be enjoyable. They are
part of the natural word that is shrinking at our expense.
Enjoy them!
An important last step before using a fumigant cartridge: read
the instructions again. Photo: A.T. Eaton
Conibear traps are steel traps that almost instantly
kill an animal that tries to move through it. If a pet or
other non-target animal walks through it, there is no second chance. Because of this, they should only be used
where you are certain the intended target is the only animal
that will enter. They are usually placed just inside the burrow, to trap the occupant as it enters or leaves. Conibear
sizes 160 and 220 are appropriate sizes for woodchucks.
Because of the potential for killing other animals, I discourage people from using Conibear traps.
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Extension as the source.
Where trade names are mentioned, no discrimination is intended and no endorsement is implied. Pesticide registrations change
frequently. For the latest information on registration of a pesticide in New Hampshire, contact the Pesticide Control Division of the NH
Dept. of Agriculture at 603-271-3550.
Thank you to David Seavey (Merrimack County Cooperative Extension) and Rob Calvert and Marsha Barden (NH Fish & Game and
USDA-APHIS Wildlife Services) for reviewing this manuscript and making helpful suggestions. You can download this publication with
color photos at our website at ceinfo.unh.edu.
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